Title: Syrtis Major, Mars

Source: U.S. Geological Survey, Flagstaff, Arizona

Information: Mosaic of the Syrtis Major Hemisphere of Mars projected into a point perspective, a view similar to that which one would see from a spacecraft. The distance is 2,000 kilometers from the surface of the planet, with the scale being 0.6 kilometers per pixel. This mosaic is composed of about 100 red and violet filter Viking Orbiter images. The images were acquired in 1980, during early northern summer on Mars. The center of the image is near latitude -2, longitude -55. The color variations have been enhanced by a factor of two, and the large-scale brightness variations (mostly due to sun-angle variations) have been normalized by large-scale filtering. The large, brightly colored area located in the upper left corner of the image is known as Arabia. The dark area to the right of Arabia, called Syrtis Major Planus, is a low-relief volcanic shield of probably basaltic composition. Bright white areas to the south, including the Hellas impact basin at lower right, are covered by carbon dioxide frost.